## 10983 - Buy one, get the rest free

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double_zero
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Posts: 8
Joined: Sat Jun 28, 2014 12:42 pm

### Re: 10983 - Buy one, get the rest free

I Keep Getting WA. could anybody help me by giving me a test case that breaks my code?

Code: Select all

``````#include <iostream>
#include <unistd.h>
#include <stdio.h>
#include <string>
#include <string.h>
#include <algorithm>
#include <functional>
#include <vector>
#include <cmath>
#include <queue>
#include <sstream>
#define INF (int)1e9
#define MAX (400+10)
#define node(city,day) ((city)*d+(day))

using namespace std;

int n, m, d;

int res[MAX][MAX],RES[MAX][MAX],cap[MAX][MAX],CAP[MAX][MAX],cost[MAX][MAX],mf,f,s=0,t=1,par[MAX];

void agument(int v, int minEdge){
if(v==s) f=minEdge;
else if(par[v]!=-1){
agument(par[v],min(minEdge,res[par[v]][v]));
res[par[v]][v]-=f; res[v][par[v]]+=f;
//cout << v << " ";
}
}

void bfs(int s, int maxcost){
memset(par,-1,sizeof par); dist.assign(MAX,INF);
dist[s]=0; queue<int> q; q.push(s);
while(!q.empty()){
int u=q.front(); q.pop();
//cout << "bfs: " << u << endl;
if(u==t) break;
int v=adj[u][i]; //cout << "->" << v << " cost: " << cost[u][v] << endl;
if(res[u][v]>0 && dist[v]==INF && cost[u][v]<=maxcost){
dist[v]=dist[u]+1; q.push(v); par[v]=u;
}
}
}
}

int main(){
int cs=1, tc; cin >> tc;
while(tc--){ cin >> n >> d >> m; d++;
//initilize
memset(cost,0,sizeof cost);
memset(RES,0,sizeof RES);
memset(CAP,0,sizeof CAP);
for(int i=0 ; i<n ; i++) adj[i].clear();
s = node(n,d); t = node(n-1,d-1);
//cout << s << " " << t << endl;
//parse input and constracting the graph
//(u,e) =c=> (v,e+1)
int u,v,c,p,e;
while(m--){
cin >> u >> v >> c >> p >> e; u--; v--;
RES[node(u,e)][node(v,e+1)]+=c; //RES[v][u]+=c;
CAP[node(u,e)][node(v,e+1)]+=c; //CAP[v][u]+=c;
cost[node(u,e)][node(v,e+1)] =p;
}
//source =Zi=> (0,i)
int zi,zs=0;
for(int i=0 ; i<n ; i++){
cin >> zi; zs+=zi;
RES[s][node(i,0)]+=zi; //RES[v][u]+=c;
CAP[s][node(i,0)]+=zi; //CAP[v][u]+=c;
cost[s][node(i,0)] =0;
}
//(u,d) =inf=> (u,d+1)
for(int i=0 ; i<n ; i++){
for(int j=0 ; j<d-1 ; j++){
RES[node(i,j)][node(i,j+1)]+=INF; //RES[v][u]+=c;
CAP[node(i,j)][node(i,j+1)]+=INF; //CAP[v][u]+=c;
cost[node(i,j)][node(i,j+1)] =0;
}
}
//binary search + max flow
int lo=0, hi=100001, mid;bool hasAns=0;
while(lo<hi){
mid = (lo+hi)/2;
//cout << "mid: " << mid << " ";
memcpy(res,RES,sizeof RES);
memcpy(res,CAP,sizeof CAP);mf=0;
while(1){
f=0; bfs(s,mid);
agument(t,INF); //cout << endl;
if(f==0) break;
mf+=f;
}
//cout << "mf: " << mf << endl;
if(mf==zs) hi=mid, hasAns=1; else lo=mid+1;
}
if(!hasAns) printf("Case #%d: Impossible\n", cs++);
else printf("Case #%d: %d\n", cs++, hi );
}
return 0;
}

``````